High-range I.Q. scores by age group

© April 2018 Paul Cooijmans

Introduction

This report focuses on performance by age on all of the tests since 1995. For each test, the median protonorms per age class are computed. For each age class the median protonorm across the tests is computed. In case of compound tests, the subtest scores are used instead of the total scores, because the "age taken" information resides at subtest level (different subtests may have been taken at different ages).

The results are presented within-sex to detect possible sex differences in the development of I.Q. with age. The available number of female scores is still too low to make this comparison significant though.

Within males

This table gives, for each age class, the median protonorm, the corresponding I.Q., and a graphical representation wherein the number of *s is (I.Q. - 110)/3.

Age class Prot. I.Q. Graph
80-84 280 119 ***
75-79      
70-74 348 129 ******
65-69 386 135 ********
60-64 387 135 ********
55-59 414 140 **********
50-54 395 137 *********
45-49 405 138 *********
40-44 423 141 **********
35-39 423 141 **********
30-34 410 139 **********
25-29 395 137 *********
22-24 411 139 **********
20-21 392 136 *********
18-19 379 134 ********
17 389 136 *********
16 380 134 ********
15 334 127 ******
14 320 125 *****
13 318 125 *****
12 297 122 ****
11      
10      
9 233 113 *

There are a bit over 4000 scores by males in total.

Within females

The following table gives, for each age class, the median protonorm, the therewith corresponding I.Q., and a graphical representation wherein the number of *s is (I.Q. - 105)/3.

Age class Prot. I.Q. Graph
75-79 355 130 ********
70-74 374 133 *********
65-69      
60-64 304 123 ******
55-59 302 122 ******
50-54 329 126 *******
45-49 427 142 ************
40-44 378 134 **********
35-39 390 136 **********
30-34 377 134 **********
25-29 355 130 ********
22-24 335 127 *******
20-21 327 126 *******
18-19 322 125 *******
17 302 122 ******
16 321 125 *******
15 337 128 ********
14 300 122 ******
13 298 122 ******
12 189 107 *

While the total number of available scores by females is a bit over 500, the highest and lowest age classes in the table have only a single score. The present amount of data is not sufficient to make the development of scores with age (seen in the table) significant, and a tabulation like this will be repeated as more scores become available. Given the rate at which scores by females come in, it may take ten years or so before it makes sense to do this again.